Autonomously operating driving safety or driver assistance systems for motor vehicles are known in different implementations. Such systems comprise sensors that record at least the area in front of the vehicle in the direction of travel by sensors, and the data thereof are analyzed in a computer by means of suitable software. Based on the information obtained by said data processing, the computer can automatically trigger and carry out the regulation of braking, speed, distance, compensation and/or deviation by means of corresponding control devices and actuators.
Prompted by EC Regulation No. 661/2009, emergency brake systems known as AEBSs (Advanced Emergency Braking Systems) are increasingly being used in commercial vehicles; said systems output visual and/or audible signals where certain brake-related sensor data are present and if necessary initiate and regulate autonomous emergency braking with a maximum possible deceleration of the vehicle in order to avoid a collision with a vehicle that is traveling or that has stopped in the area in front of the vehicle or with a stationary obstacle, or at least to reduce the consequences of an impending collision.
In such an emergency brake system, such as for example the known emergency brake system OnGuardPLUS® of the applicant, for safety reasons a checking process should initially be carried out each time following the switch-on of the engine ignition, during which the sensor data and parameter settings that are necessary for the operation of the driving safety or driver assistance system are checked for the plausibility thereof. As a result, there is a conflict between the required complete functional safety and the immediate availability of the emergency brake system, since the driving safety or driver assistance system is only operationally ready and is only released as being functionally safe following the completion of the checking process. During the first kilometers or minutes of driving after the start, i.e. during the checking process, such a driving safety or driver assistance system is therefore deactivated. This can be indicated to the driver by a yellow warning light. Such a warning light indicator is obligatory for an inactive emergency brake system, at least in the commercial vehicle field. However, this is potentially perceived by a driver of a motor vehicle as disturbing or irritating. Moreover, the driving safety or driver assistance system is only available with a time delay after the commencement of travel.
An electronic driving dynamics regulating system of a land vehicle for steering and braking intervention, with which a yaw rate and/or a lateral acceleration of the subject vehicle is/are detected by means of a sensor arrangement, is known from EP 1 934 075 B1. Said data are checked for the plausibility thereof within a period of time that is shorter than half a second, and said data are then incorporated as actual variables in a calculation of driving dynamics target values of the driving dynamics regulating system. During the plausibility check of the signals, the brake forces of a brake system and/or the steering forces of a steering device of the vehicle are each limited to a level that is assessed as being non-critical for the safety of the vehicle.